Would that mean there was no way Trump could have lost? No.
It is unclear how using counties as a metric is useful. It would be quite significant if Clinton won the equivalent of the population of LA county over Trump.
The popular vote is a relevant example of how the contest was not inevitable. More people voted for Hillary than for Trump... that's not what wins the election, but it's not meaningless to a democratic society. Counties, however, are completely arbitrary. Should winning the least populous 51% of counties matter to anyone?
You're using it as a convenient way to sidestep the obvious implication of losing the popular vote.
It's about as useful as referring to the popular vote in a contest that clearly established beforehand that it would not be considered.